In 3GPP (3rd Generation Partnership Project), W-CDMA system has been standardized as the third generation cellular mobile communication system and sequentially put into service. In addition, HSDPA with a still higher communication speed has been standardized and put into service.
In 3GPP, on the other hand, standardization of Evolved Universal Terrestrial Radio Access (referred to as “EUTRA”, in the following) is underway. As the downlink communication system of EUTRA, OFDM (Orthogonal Frequency Division Multiplexing) system which is robust against multi-path interference and suitable for high-speed transmission has been adopted. In addition, as the uplink communication method, DFT (Discrete Fourier Transform)-spread OFDM system of an SC-FDMA (Single Carrier-Frequency Division Multiple Access) system which can reduce PAPR (Peak to Average Power Ratio) of transmission signals has been employed, considering the cost and power consumption of the mobile station apparatus.
Additionally, in 3GPP, discussions on Advanced-EUTRA, a further evolution of EUTRA, have begun. In Advanced-EUTRA, it is assumed to perform communication at a maximum downlink transmission rate of 1 Gbps or more and a maximum uplink transmission rate of 500 Mbps or more, using a band with a bandwidth of up to 100 MHz for each of uplink and downlink.
It is considered in Advanced-EUTRA to realize a 100 MHz band by bundling a plurality of 20 MHz bands of EUTRA so that mobile station apparatuses of EUTRA can also be accommodated. In Advanced-EUTRA, a band of EUTRA not exceeding 20 MHz is referred to as a Component Carrier (CC) (see non-patent document 3).    Non-patent document 1: 3GPP TS (Technical Specification) 36.300, V8.80 (2009-03), Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN), Overall description Stage2    Non-patent document 2: 3GPP TS (Technical Specification) 36.321, V8.50 (2009-03), Evolved Universal Terrestrial Radio Access (E-UTRA) Medium Access Control (MAC) protocol specification    Non-patent document 3: 3GPP TR (Technical Specification) 36.814, V0.41 (2009-02), Evolved Universal Terrestrial Radio Access (E-UTRA) Radio Resource Control (RRC) Protocol specification